SuneF wrote:Usually Black cannot afford to make multiple consecutive "nothing moves". Almost all those positions will be lost.
I am not sure I follow this. Basically you seem to say that null move does not work, (if I understand correctly that with "nothing moves" you mean null moves). But we know that it does: very often null move fails high, because the side that fails low plays the all nodes, and plays every conceivable blunder under the sun there. Moves that accomplish something are rare, most moves only suck him deeper into the sh*t he is already in. Null move is by far the largest source of beta cutoffs.
It's like saying White can capture two pieces for free. So there is a very tiny probability that you get a fail high anyway and therefore it's best to skip this nonsense quickly by e.g. repetition.
Statistically it is more likely white will blunder away two more pieces for free. The point is, that to make someone fail low, you have to refute _all_ his moves. The sensical as well as the non-sensical. The non-sensical ones are abundant, and you would like to refute them by null moves. Sequences of non-sensical moves you would like to refute with sequences of null moves. Everything else is a waste of nodes. That he has some sequences of moves that pose a threat bad enough that you cannot afford to keep up the null moving is bad enough, but no reason to be soft in refuting is non-sense branches.
However by resetting the repetition counter you also eliminate the possibility of other repetitions, which can lead to a larger subtree.
Which effect is greater is unclear to me, yours a magnitude larger but equally rarer.
Well, I did not say you should reset the repetition counter, did I? How could you possibly recognize null-spanning repeats and score them as high-failing draws for the side that was doing them, when you would reset that counter? But my point was that it is of no importance what effect is larger.